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Soil aggregates are important for improving the soil quality and structure. Soil erosion causes the fragmentation and migration of soil aggregates. Vegetation restoration is an effective method for controlling soil erosion, and the vegetation distribution on the slope changes the hydrological processes. However, there is a dearth of studies investigating the regulation of vegetation patterns in relation to soil aggregate loss. This study employed a physical model of a slope gully system to examine the characteristics of soil aggregates loss during erosion processes under four distinct vegetation patterns: no vegetation (pattern A), up‐slope vegetation (pattern B), middle‐slope vegetation (pattern C), and down‐slope vegetation (pattern D), utilizing simulated rainfall experiments. The results showed that under various patterns of vegetation, the loss of soil aggregates is predominantly driven by microaggregates (<0.25 mm), A (65.2%) < B (72.4%) < C (77.7%) < D (87.7%). On the contrary, there is an opposite trend of change observed in macroaggregates(>0.25 mm). The vegetation pattern had different effects on the enrichment rate of aggregates in sediments: the enrichment ratio of macroaggregates decreased by 20.9%–64.7% and the enrichment ratio of microaggregates increased by 11.1%–34.5%. The cumulative loss of soil aggregates and the cumulative runoff volume can be described by a linear equation: y = ax + b, where 'a' denotes the rate of soil aggregate loss. Vegetation patterns had the capacity to decrease the rate of macroaggregate loss. Among these patterns, pattern D exhibits the lowest rate, followed by patterns C, B, and A. These results indicated that down‐slope vegetation pattern is effective in reducing the loss of soil aggregates especially macroaggregates. [ABSTRACT FROM AUTHOR]

Excellent morphology and low harmful defect states of the absorber layer are essential to fabricate the high‐performance Cu2ZnSn(S, Se)4 (CZTSSe) devices. Herein, the annealing time of precursor films in air is proved to have much impact on the quality of absorber layer and the performance of devices. Appropriately extending the air‐annealing time can promote the diffusion of Na into films and O absorption on the surface of precursor films, boost the growth of crystal grain, and lessen the harmful defect density and band‐tailing states of absorber. The appropriate extension of air‐annealing time also regulates the electrical properties of the absorber. The efficiency of CZTSSe devices is enhanced from 6.92% (1 min) to 10.1% (7 min), with the decreased VOC, Def. These enhanced properties demonstrate that regulating the air‐annealing time of precursor films can be a simple and direct way for improving the performance of CZTSSe devices. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C3N4) is considered as an ideal semiconductor for photocatalytic H2O2 production due to its abundant raw materials, facile synthesis, and convenient structure regulation. However, in terms of photocatalysis, pristine carbon nitride (CN) is limited by fast electron–hole pair recombination and low utilization of visible light. Herein, we optimized the electronic structure by intercalating K ions into the g-C3N4 layers and introducing nitrogen defects, which achieved remarkable results. A simple KOH-assisted thermal carbon nitride polymerization method was used to achieve the one-step synthesis of K-intercalated polymeric carbon nitride (K-CN), resulting in a maximum H2O2 productivity of 19 663 μmol L−1 h−1 (14 times that of CN) and apparent quantum efficiency of 15.37%. In this strategy, on the one hand, the K ion intercalation optimizes the internal energy band structure, narrowing the bandgap from 2.82 eV to 2.73 eV; on the other hand, because of the strong electronegativity of the N atom in –C≡N, K2-CN has an obvious ability to trap electrons to inhibit charge recombination. This research presents a promising synthetic route through K ion doping to better manipulate the electronic structure of g-C3N4, which offers a reference for further improving the performance of photocatalytic H2O2 and understanding its generation mechanism. [ABSTRACT FROM AUTHOR]